MARSBUGS: The Electronic Astrobiology Newsletter Volume 8, Number 1, 8 January 2001. Editors: Dr. David J. Thomas, Math and Science Division, Lyon College, Batesville, AR 72503-2317, USA. dthomas@lyon.edu Dr. Julian A. Hiscox, School of Animal and Microbial Sciences, University of Reading, Reading, RG6 6AJ, United Kingdom. J.A.Hiscox@reading.ac.uk Marsbugs is published on a weekly to quarterly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editors, except for specific articles, in which instance copyright exists with the author/authors. While we cannot copyright our mailing list, our readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing list. The editors do not condone "spamming" of our subscribers. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editors. E-mail subscriptions are free, and may be obtained by contacting either of the editors. Article contributions are welcome, and should be submitted to either of the two editors. Contributions should include a short biographical statement about the author(s) along with the author(s)' correspondence address. Subscribers are advised to make appropriate inquiries before joining societies, ordering goods etc. Back issues and Adobe Acrobat PDF files suitable for printing may be obtained from the official Marsbugs web page at http://welcome.to/marsbugs. The purpose of this newsletter is to provide a channel of information for scientists, educators and other persons interested in exobiology and related fields. This newsletter is not intended to replace peer- reviewed journals, but to supplement them. We, the editors, envision Marsbugs as a medium in which people can informally present ideas for investigation, questions about exobiology, and announcements of upcoming events. Astrobiology is still a relatively young field, and new ideas may come from the most unexpected places. Subjects may include, but are not limited to: exobiology and astrobiology (life on other planets), the search for extraterrestrial intelligence (SETI), ecopoeisis and terraformation, Earth from space, planetary biology, primordial evolution, space physiology, biological life support systems, and human habitation of space and other planets. --------------------------------------------------------------------- CONTENTS 1) ROSETTA'S CHRISTMAS PRESENT TO MARS EXPRESS From ESA Science News 2) EXTREMELY EFFICIENT NUCLEAR FUEL COULD TAKE MAN TO MARS IN JUST TWO WEEKS Ben-Gurion University of the Negev release 3) THE CASE OF THE MISSING MARS WATER From NASA Science News 4) MARS 2001 ODYSSEY SPACECRAFT ARRIVES FOR LAUNCH PREPARATION JPL release 5) UA TEAM TAKES ITS MARS-BOUND EXPERIMENT TO CAPE CANAVERAL By Lori Stiles 6) NASA INTEGRATED ACTION TEAM REPORT AVAILABLE NASA note N01-03 7) NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas 8) CASSINI WEEKLY SIGNIFICANT EVENTS JPL release 9) CASSINI MISSION STATUS JPL release 10) THIS WEEK ON GALILEO JPL release 11) ISS STATUS REPORT JSC release 12) STARDUST STATUS REPORT JPL release --------------------------------------------------------------------- ROSETTA'S CHRISTMAS PRESENT TO MARS EXPRESS From ESA Science News http://sci.esa.int 25 December 2000 On 25 December 2003, ESA's Mars Express orbiter will arrive in orbit around the Red Planet after releasing a small lander named Beagle 2 onto its rust-colored, dusty deserts. This wonderful Christmas present for planetary scientists would not have been possible without major contributions from another ESA project-the Rosetta comet chaser. Although both missions are due for launch in 2003, their backgrounds are very different. Mars Express is a medium-sized mission, one of the pioneers in ESA's efforts to build faster, cheaper, space science missions. Rosetta is a more ambitious, more expensive, Cornerstone mission, which will spend more than a decade travelling through the Solar System in an effort to unravel the secrets of Comet Wirtanen. Mars Express is the first of the ESA's new "flexible" missions. With a total budget of just 150 million Euro (1996 prices), it will be built and launched for about half the cost of similar, previous missions. However, this has only been made possible by re-using existing hardware, adopting new project management practices, shortening the design and development time, and minimizing launcher costs. In particular, Mars Express is making maximum use of pre-existing "off-the-shelf" technology and hardware that has already been developed for the Rosetta Orbiter. About 60% of the technology on the Mars Express spacecraft has been "borrowed" from Rosetta (see table). This includes such vital components as the onboard computer, the low gain antenna for communication with Earth, and the gyroscopes that control the spacecraft's attitude. Mars Express hardware items in common with Rosetta: * Command and data handling system (on-board computer) * Transponder (transmitter and receivers in S and X band) * Low gain antenna * Gyroscopes and accelerometers * Solar array drive mechanism, a motor and gearbox to rotate each array by more than one turn in each direction * Power control unit to ensure maximum power generation by the solar array * Power distribution unit to distribute power to all on-board consumers and avoid short circuits should one of them fail. * Remote terminal units to interface a system, such as the sun sensor or science instruments, with the on-board computer. * Interface unit to the on-board computer for attitude determination sensors * Star Tracker "What we are doing with Mars Express will affect flexible missions at the agency, which may in future be linked more closely to major missions," said Rudi Schmidt, Mars Express Project Manager. "In this way, we are able to make savings without taking big risks." "A further advantage is that 'commonalities' with Rosetta and its payload make it possible to streamline management methods by handing over more responsibility to industry," he added. "Rosetta will spend 11 years in deep space, travelling almost as far as the orbit of Jupiter before entering orbit around the comet's nucleus and then flying alongside the comet on its journey towards the Sun," explained John Ellwood, Rosetta's Project Manager. "Such a complex, groundbreaking mission requires the maximum reliability and the highest specifications for its components. We are delighted to be able to share these new technologies with our colleagues on Mars Express." Useful links for this story * Rosetta homepage http://sci.esa.int/rosetta * Mars Express homepage http://sci.esa.int/marsexpress Image captions [Image 1] Planet Mars. http://sci.esa.int/content/searchimage/searchresult.cfm?aid=13&cid=12 &ooid=25517 [Image 2] The Rosetta lander. http://sci.esa.int/content/searchimage/searchresult.cfm?aid=13&cid=12 &ooid=12159 [Image 3] Mars Express Orbiter. http://sci.esa.int/content/searchimage/searchresult.cfm?aid=13&cid=12 &ooid=17935 --------------------------------------------------------------------- EXTREMELY EFFICIENT NUCLEAR FUEL COULD TAKE MAN TO MARS IN JUST TWO WEEKS Ben-Gurion University of the Negev release 28 December 2000 Scientists at Ben-Gurion University of the Negev have shown that an unusual nuclear fuel could speed space vehicles from Earth to Mars in as little as two weeks. Standard chemical propulsion used in existing spacecraft currently takes from between eight to ten months to make the same trip. Calculations supporting this conclusion were reported in this month's issue of Nuclear Instruments and Methods in Physics Research A (455: 442-451, 2000) by Professor Yigal Ronen, of BGU's Department of Nuclear Engineering and graduate student Eugene Shwagerous. In the article, the researchers demonstrate that the fairly rare nuclear material americium-242m (Am-242m) can maintain sustained nuclear fission as an extremely thin metallic film, less than a thousandth of a millimeter thick. In this form, the extremely high- energy, high-temperature fission products can escape the fuel elements and be used for propulsion in space. Obtaining fission- fragments is not possible with the better-known uranium-235 and plutonium-239 nuclear fuels: they require large fuel rods, which absorb fission products. Ronen became interested in nuclear reactors for space vehicles some 15 years ago at a conference dedicated to this subject. Speaker- after-speaker stressed that whatever the approach, the mass (weight) of the reactor had to be as light as possible for efficient space travel. At a more recent meeting, Professor Carlo Rubbia of CERN (Nobel Laureate in Physics, 1984) brought up the novel concept of utilizing the highly energetic fragments produced by nuclear fission to heat a gas; the extremely high temperatures produced would enable faster interplanetary travel. To meet the challenge of a light nuclear reactor, Ronen examined one element of reactor design, the nuclear fuel itself. He found at the time that of the known fission fuels, Am-242m is the front-runner, requiring only 1 percent of the mass (or weight) of uranium or plutonium to reach its critical state. The recent study examined various theoretical structures for positioning Am-242m metal and control materials for space reactors. He determined that this fuel could indeed sustain fission in the form of thin films that release high-energy fission products. Moreover, he showed how these fission products could be used themselves as a propellant, or to heat a gas for propulsion, or to fuel a special generator that produces electricity. "There are still many hurtles to overcome before americium-242m can be used in space," Ronen says. "There is the problem of producing the fuel in large enough quantities from plutonium-241 and americium- 241, which requires several steps and is expensive. But the material is already available in fairly small amounts. In addition, actual reactor design, refueling, heat removal, and safety provisions for manned vehicles have not yet been examined. "However, I am sure that americium-242m will eventually be implemented for space travel, as it is the only proven material whose fission products can be made available for high speed propulsion. Indeed, Carlo Rubbia has also recognized that this is the most probable fuel that will be getting us to Mars and back. I think that we are now far enough advanced to interest international space programs in taking a closer look at americium-based space vehicles." For photographs, please contact: Amir Rozenblit, BGU Spokesman Phone: 972-8-6461802 or 972-8-6477717/6 Fax: 972-8-6472803 E-mail: rosenbli@bgumail.bgu.ac.il For further information, please contact: E. Tepper, Department of Public Affairs Phone: 972-8-646-1283 Fax: 972-8-647-2937 E-mail: tepperel@bgumail.bgu.ac.il --------------------------------------------------------------------- THE CASE OF THE MISSING MARS WATER From NASA Science News 5 January 2001 Mars may once have been a very wet place. A host of clues remain from an earlier era, billions of years ago, hinting that the Red Planet was host to great rivers, lakes and perhaps even an ocean. But some of the clues are contradictory-they don't all fit together in a coherent whole. Little wonder, then, that the fate of water on Mars is such a hotly debated topic. The reason for the intense interest in martian water is simple: without water, there can be no life as we know it. If it has been 3.5 billion years since liquid water was present on Mars, the chance of finding life there is remote. But if water is present on Mars now, however well hidden, life may be holding on in some protected niche. Based on what we have observed so far, Mars today is a frozen desert. It's too cold for liquid water to exist on its surface and too cold to rain. The planet's atmosphere is also too thin to permit any significant amount of snowfall. Even if some internal heat source warmed the planet up enough for ice to melt, it wouldn't yield liquid water. The martian atmosphere is so thin that even if the temperature rose above freezing the ice would change directly to water vapor. Signs of heavy flooding But there must have been water, and plenty of it, in Mars's past. That is evident from the massive outflow channels that are found, mostly, in the northern lowlands. The intensity of the floods that carved these channels was tremendous, perhaps reaching discharge rates as high as 10,000 times that at which the Mississippi, when flooded, pours into the Gulf of Mexico. What caused these giant floods? Was it a climate change, perhaps brought about by a change in Mars's orbit? Or was the planet's own internal heat responsible? And, whatever mechanism caused the floods in the first place, where has all that water gone? Was it absorbed into the ground where it remains today, frozen? Or did it dissipate into the martian atmosphere, where it was subsequently lost to space? No one knows for certain the answers to these questions. Some scientists believe that the catastrophic floods that carved the outflow channels occurred nearly simultaneously, releasing such vast quantities of water that they merged into an ocean that covered the northern lowlands. Tim Parker of NASA's Jet Propulsion Laboratory first proposed such an idea in 1989. Parker, examining images taken by the Viking Orbiters, found what he believed were remnants of two ancient ocean shorelines, which he called "contacts," one inside the other, in the martian north. Expanding on this notion, in 1991 Vic Baker of the University of Arizona, suggested that Mars might not be geologically dead and permanently frozen. Instead, he proposed, Mars might undergo cycles, or pulses-first heating up, releasing groundwater and forming an ocean in the north, then dissipating the ocean back into the planet's crust and re-freezing. More recently, Jim Head and colleagues at Brown University, found evidence that is consistent with a shoreline that might indeed have existed at the inner of Parker's two proposed contacts, contact 2. Head and colleagues examined elevation data gathered by the Mars Orbiter Laser Altimeter (MOLA) on board the Mars Global Surveyor (MGS) and found that the elevation at points along contact 2 were much closer to a straight line than those at contact 1. They also found that the terrain below this elevation was smoother than the terrain above it. Both of these findings are consistent with the former presence there of an ocean. But the story doesn't end there. Shortly after Head and colleagues published their findings, Mike Malin and Ken Edgett of Malin Space Systems used the Mars Orbital Camera (MOC) aboard MGS, to take a series of high-resolution images of contact 2 terrain. Their conclusion: there's nothing there. And the debate continues. Says Mike Carr of the U.S. Geological Survey, author of the book Water on Mars, "We're getting all this new data from MGS, and I think a lot of it is just not understood yet. It's very hard to understand. The whole business of the oceans, the evidence is so contradictory." Mysterious valleys Mars's small-valley networks, which occur mainly in the southern highlands, pose another perplexing problem. Scientists who first studied images of these valleys thought they resembled river valleys on Earth. So, they reasoned, a similar process, the runoff of rainwater, must have formed them. For Mars to be warm enough to rain, however, it would have needed a much thicker atmosphere than it has today. And no one has come up with a clear-cut explanation for how such an atmosphere could have formed. One alternative theory is that a process known as sapping, or collapse caused by the softening of the soil by groundwater, created the valleys. Yet another notion is that perhaps glaciers covered the regions around the valleys, and that glacial meltwater carved them. As with Mars's other watery mysteries, however, the question of how the valley networks formed remains unanswered. And if these vexing problems weren't enough, recent images from MOC reveal a startling new puzzle. In nearly a dozen different locations on Mars-all of them far from the equator-there are signs that water has been seeping out of the walls of valleys and craters, forming small gullies. Some scientists speculate that this activity is very recent, perhaps occurring within the past 10 years; others say 10 million years is more likely. Yet many aspects of these seepage gullies defy common sense. "They sure look like water-worn features," says Mike Carr, "but they seem to contradict what we know about the stability of water." They occur not only in the coldest regions on Mars, but on slopes facing away from the Sun, where the temperature rarely gets above minus 50 degrees Centigrade. Yet the water appears to be seeping out from only 100 meters below the surface, a depth at which scientists previously believed Mars's crust to be frozen solid. Scientists are busily working to devise an explanation for this phenomenon. There is one additional thorn in the side of those who study water on Mars. No evidence of carbonates has yet been found anywhere on the planet. Carbonates are minerals that form readily when liquid water reacts with carbon dioxide in the atmosphere. If Mars had abundant liquid water in its past, carbonates should be detectable in the martian rock record. The Thermal Emission Spectrometer (TES) instrument aboard MGS was designed to look for just such a signature. But so far it has found none. Perhaps other evaporites, such as sulfates (as detected in martian meteorites and interpreted from landing site analyses), are the dominant material of this type on Mars. What next? New debates will undoubtedly emerge as data from Mars Global Surveyor is digested. In 2001, NASA will send a new orbiter to Mars, which will include a higher-resolution spectrometer to search for carbonates. In 2003, NASA will send two rovers to Mars to hunt for water's signatures in rocks and soil on the surface. But many questions about the history of water on Mars are likely to remain unanswered until samples are returned from the Red Planet for examination on Earth. Says Carr, "I think the sample return is what we want, particularly of sediments. And if we could get samples of things like this back on Earth, I think it would do an awful lot to help us understand what's going on [on Mars]." For more information on this article, see http://science.nasa.gov/headlines/y2001/ast05jan_1.htm?list52260. --------------------------------------------------------------------- MARS 2001 ODYSSEY SPACECRAFT ARRIVES FOR LAUNCH PREPARATION JPL release 5 December 2001 The first major step toward NASA's return of a spacecraft to an orbit around Mars was achieved late Thursday night, Jan. 4, when the Mars Odyssey spacecraft arrived at NASA's Kennedy Space Center in Florida. The spacecraft was shipped aboard an Air Force C-17 cargo airplane from Denver, CO, location of the Lockheed Martin plant where the spacecraft was built. The project is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA. Mars Odyssey was moved on a transport trailer from the Shuttle Landing Facility to the Kennedy Space Center's Spacecraft Assembly and Encapsulation Facility 2, where it will undergo final assembly and checkout. This includes installation of two of the three science instruments, integration of the three-panel solar array, and a spacecraft functional test. It will be fueled and then mated to an upper stage booster, the final activities before going to the launch pad. Launch is planned for April 7, the first day of a 21-day launch opportunity. Mars Odyssey will be inserted into an interplanetary trajectory by a Boeing Delta II launch vehicle from Pad A at Complex 17. The spacecraft will arrive at Mars on October 20, 2001, for insertion into an initial elliptical capture orbit. Its final operational altitude at Mars will be a 400 kilometer-high (250 mile-) Sun-synchronous polar orbit. Mars Odyssey will conduct a two-year mission in Mars orbit mapping the planet's surface and measuring its environment. "Ultimately, the spacecraft could contribute significantly toward understanding what may be necessary for a more sophisticated exploration of Mars, and perhaps an eventual human visit," said Mars Odyssey Project Manger George Pace of JPL. The program management of the Mars Odyssey mission is by the Office of Space Science at NASA Headquarters, Washington, DC. NASA's Kennedy Space Center manages the launch. Contacts: Mary Hardin, JPL, 818-354-0344 George H. Diller, KSC, 321-867-2468 --------------------------------------------------------------------- UA TEAM TAKES ITS MARS-BOUND EXPERIMENT TO CAPE CANAVERAL By Lori Stiles University of Arizona release 5 January 2001 A team at the University of Arizona Lunar and Planetary Laboratory (LPL) is gripped by the special frenzied excitement that comes with packing up a major space experiment scheduled to reach Mars next October. William V. Boynton and his team started work on the Gamma Ray Spectrometer in August 1997. It is one of three science instruments to go on NASA's 2001 Mars Orbiter, scheduled for launch Saturday, April 7. If launch goes as scheduled, the orbiter will arrive at Mars on October 20, 2001. The team will begin packing the gamma ray sensor head this weekend, said Heather Enos, senior program coordinator at LPL. Senior systems engineer Chuck Fellows must attach accelerometers on the sensor head to record all shocks and vibrations during the 4-day haul in a 48- foot semi from Tucson to Kennedy Space Center at Cape Canaveral, FL. It will take all day Monday (January 8) to finish crating the sensor head and central electronics box. In addition to this flight hardware, there's another nine times as much auxiliary hardware that must be packed and ready on the LPL loading dock at 7:00 AM Tuesday (January 9). Auxiliary hardware includes an elaborate, UA-built bench top cooler that simulates space environment, which the team will use at the Cape in a thorough, 10-day test needed to verify that all arrived safely. Bob Marcialis and Rick Schmidt will drive a follow car escorting the semi truck to Florida, leaving Tuesday morning and arriving Friday, (January 12). Boynton and 10 more from his group will fly to Florida to meet them. The team will unload, unpack and assemble their stand- alone lab to begin instrument verification tests Monday, January 15. They will first test the central electronics box so it can be mounted on the orbiter spacecraft on Tuesday, January 16. They then begin the 10-day verification test on the gamma ray sensor head, which is to be installed on the orbiter January 31. The Gamma Ray Spectrometer (GRS) will fulfill the commitment to re- fly all the investigations of the attempted Mars Observer mission of 1994. Its science goals are: * to quantitatively determine the elemental abundances of the martian surface, including composition of the permanent polar caps * to map the distribution of water and to determine its near-surface stratigraphy * to determine the thickness of the seasonal polar caps and their variation with time * to study the nature of cosmic gamma-ray bursts The LPL team GRS web site is at http://nemesis.lpl.arizona.edu. Last March, the Smithsonian Institution added Boynton's Mars-mapping project to its permanent research collection on information technology in the Smithsonian National Museum of American History. Boynton and his group intend to build a 3-dimensional map, or globe, of the surface of the planet Mars with GRS data. The map will visually present the elemental composition of Mars' surface and near- surface so that users can retrieve information on a particular region anywhere on the global map via the Internet. Research scientists and advanced science students-and, later, students still in grade school- will be able to interactively learn using the map, project team members say. The 2001 Mars Odyssey mission is managed by the Jet Propulsion Laboratory in Pasadena, CA, for NASA's Office of Space Science. JPL is a division of the California Institute of Technology. Related links JPL's 2001 Mars Odyssey web site is at http://mars.jpl.nasa.gov/2001/new/orbiter/index.html Images supporting this release are available at http://uanews.opi.arizona.edu/cgi- bin/WebObjects/UANews.woa/wa/SRStoryDetails?ArticleID=2903 Contacts: William V. Boynton, 520-621-6941, wboynton@lpl.arizona.edu Heather Enos, 520-621-8279, heather@gamma1.lpl.arizona.edu --------------------------------------------------------------------- NASA INTEGRATED ACTION TEAM REPORT AVAILABLE NASA note N01-03 5 January 2001 A report by the NASA Chief Engineer and the NASA Integrated Action Team, "Enhancing Mission Success-A Framework for the Future," is available at ftp://ftp.hq.nasa.gov/pub/pao/reports/2001/NIAT.pdf. The NIAT report results from an effort started in March by the NASA Chief Engineer to develop an integrated plan addressing recommendations from reports on the Mars program, space shuttle wiring issues and a generic assessment of NASA's "Faster, Better, Cheaper" practices, and formulating actions for improvement from an agency perspective. Contact: Sarah Keegan NASA Headquarters, Washington, DC Phone: 202-358-1902 --------------------------------------------------------------------- NEW ADDITIONS TO THE ASTROBIOLOGY INDEX By David J. Thomas http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology.h tml 8 January 2000 Articles about astrobiology, exobiology and terraformation http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s1.html G. V. Levin and P. A. Straat, 1979. Completion of the Viking labeled release experiment on Mars. Journal of Molecular Evolution, 14:167- 183. G. V. Levin, L. Kuznetz and A. Lafleur, 2000. Approaches to resolving the question of life on Mars. Proceedings of SPIE - The International Society for Optical Engineering. San Diego, CA. NASA Science News, 2001. The case of the missing Mars water. NASA Science News. R. K. Obousy, A. C. Tziolas and M. R. Sims, 1999. Searching for Extant Life on Mars-The ATP-Firefly Luciferin/Luciferase Technique. SpaceDaily, 2000. Doubt cast on life on Mars. SpaceDaily. SpaceDaily, 2000. New information supports claim Viking discovered life in 1976. SpaceDaily. Articles about the biology of extreme environments (on Earth) http://www.lyon.edu/webdata/users/dthomas/astrobiology/online_article s2.html M. Bennett, 1998. Enchanting creatures. New Scientist. J. Copley, 1998. Putting life on hold. New Scientist. J. Copley, 1999. Indestructible. New Scientist. D. Dooling, 1999. Search for life on Mars will start in Siberia. NASA Science News. New Scientist, 1998. The bugs that just refused to die. New Scientist. Astrobiology and extreme environments book list http://www.lyon.edu/webdata/users/dthomas/astrobiology/astrobiology_b ooks.html M. Eigen, R. Winkler-Oswatitsch and P. Woolley, 1996. Steps Towards Life: A Perspective on Evolution. Oxford University Press, Oxford. I. Fry, 2000. The Emergence of Life on Earth: A Historical and Scientific Overview. Rutgers University Press, New Brunswick. M. Gross, 2001. Life on the Edge: Amazing Creatures Thriving in Extreme Environments. Perseus Books, New York. N. Lahav, 1998. Biogenesis: Theories of Life's Origins. Oxford University Press, Oxford. J. I. Lunine, 1999. Earth: Evolution of a Habitable World. Cambridge University Press, Cambridge. --------------------------------------------------------------------- CASSINI WEEKLY SIGNIFICANT EVENTS JPL release 20 December 2000 - 3 January 2001 The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday, January 3. The Cassini spacecraft is in an excellent state of health and is operating normally. The speed of the spacecraft can be viewed on the "Present Position" web page at http://www.jpl.nasa.gov/cassini/english/where/. On Tuesday December 19, the C23 sequence was halted with the program remaining on board, instruments placed in a safe configuration, and the spacecraft directed to Earth point in response to the autonomous swap from reaction wheels to thrusters for attitude control that occurred on December 15. Attitude Control engineers performed a series of in-flight diagnostic tests to further understand the performance of the second reaction wheel that had exhibited larger than expected drag during the previous week's observations. All tests were nominal. Extensive discussions with the wheels' manufacturer and JPL experts were undertaken and it is believed that the likely cause of the autonomous shutdown of the wheels was inadequate distribution of lubrication in the bearings due to extended operation at low speeds. On Thursday, December 21, the spacecraft was returned to RWA control, but only to maintain Earth pointing without resuming the science sequence. The wheels were monitored for the next six days with no problems observed. Additional activities in this period included Command & Data Subsystem (CDS)-A and CDS-B Autonomous SSR Memory Load Partition Repairs, Attitude and Articulation Control Subsystem (AACS) SPOT LIST Memory Readout (MRO) to read out additional data from the AACS Extended Body Star ID test, AACS Highwater Mark clears, and enabling of Ultraviolet Imaging Spectrometer (UVIS) Science Data. On Thursday, December 28, the C23 background sequence was reactivated. Real-time activities included playback pointer reset to recover the previous night's "observation" period, Composite Infrared Spectrometer (CIRS) to Science Mode, C23 Background Sequence / SSR overlay Mini-sequence Activation Immediate/Delayed Action Program (IDAP), RWA2 Bias Overlay IDAP, Imaging Science Subsystem (ISS) and Ultraviolet Imaging Spectrometer (UVIS) Instrument Expanded Block (IEB) Loads, and AACS Highwater Mark clear. All commands were verified to be successfully received at the spacecraft. The expected telemetry mode change was observed by project personnel along with spacecraft slew start back to Jupiter at the correct time indicating correct initiation of the background sequence. Saturday, December 30, began the Phase E portion of C23. Activities included Jupiter Observations of the Rings at 60 degrees phase angle, Atmospheric cyclic, CIRS Feature Track, and Ring Plane Crossing. Jupiter closest approach occurred at 02:04 PST, Spacecraft Event Time. This was followed by IO Eclipse imaging activities, Europa imaging activities, uplink of IEB loads for ISS and VIMS, Jupiter Rings (75 degree phase angle) observation, CIRS Feature track observation, imaging activities of Europa and Ganymede, Cassini Plasma Spectrometer (CAPS) Solar Wind activity, AACS Highwater Mark Clear, RWA #2 Overlay bias for DOY 004, Radio Science Ka-Band transmitter OFF and RADAR Power On, and the RADAR Synchrotron Radiation activity. The big event for RADAR during the next three months is the observation of Jupiter's synchrotron emission. This observation will be done jointly in space and on the ground using Cassini, the Deep Space Network (DSN), and the Very Large Array (VLA) antennas. The Radar observations of Jupiter serve two separate purposes. First, Jupiter offers a unique opportunity to calibrate the radiometer. Because of the proximity of the spacecraft to Jupiter, the Jovian atmospheric thermal emission will fill the antenna beam providing the basis to calibrate the radiometer system. The calibration is further enhanced by simultaneous multi-band observations by the DSN. The second purpose is related to observations of Jupiter's synchrotron emission. Jupiter's synchrotron emission originates with the relativistic electrons trapped in Jupiter's inner radiation belts. This emission has been studied by radio telescopes at various frequencies since the 1960s. Monitoring by the DSN and synchrotron emission maps by the VLA significantly advanced the understanding of Jupiter's magnetosphere in recent years. Cassini offers an opportunity to observe and map the synchrotron emission at a new frequency (13.8 GHz) not possible from Earth based telescopes. A preliminary review of the data indicates that the VLA observations were successful. Preliminary maps of Jupiter (and the synchrotron emission) at 20 and 90 cm wavelengths have been generated. Cassini Radar observations are at 2 cm (for reference). Both the 90 and 2 cm observations are new results, although some work has been done in the past at 90 cm (but without the full capabilities of the VLA). A total of 89,902 RADAR Science SABs (data packets) were received. Instrument Operations and the Multi Mission Image Processing Laboratory have produced and delivered 15910 ISS images (10251 Narrow Angle Camera and 5659 Wide Angle Camera), and 1915 VIMS cubes since the start of the Jupiter encounter period. CDA reported that their observation of the Jovian dust stream phenomenon as part of the joint Galileo-Cassini dust stream investigation was successful. Radio and Plasma Wave Science (RPWS) personnel have observed numerous outbound and inbound bow shock crossings from December 28 through January 3. CAPS ion data and electron data also confirm crossings throughout this period. The Preliminary Sequence Integration & Validation (PSIV) approval meeting was held this week for Cruise 24. Cruise 25 is still in the Sub Sequence Generation (SSG) phase. The first post-Jupiter Science Planning Virtual Team (SPVT) work for C26 started this week. This activity will follow the new eight-week development schedule for cruise sequences. The C26 sequence covers the period from April 30, 2001 through July 8, 2001. Outreach presented "Jupiter in Myth, History, and Science" to a standing-room-only crowd at Pasadena City College on December 30. The production included a reading of Ovid's creation myth involving Jupiter, King of the Gods, an appearance by Galileo Galilei, a presentation on the development and current level of understanding of Jupiter as a planetary system, and a live telephone call from Sir Arthur C. Clarke to mark the turn of the millennium. The "Saturn Educator Guide," which has been available for download for several months, is now available in printed and CD-ROM versions. KCET's "Life and Times" featured Cassini and Galileo Jupiter science results this week. An article on the joint Cassini/Galileo observations of Jupiter appeared in the L. A. Times and is available at http://www.latimes.com/news/science/science/20001231/t000124577.html. Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, CA, manages the Cassini mission for NASA's Office of Space Science, Washington, DC. --------------------------------------------------------------------- CASSINI MISSION STATUS JPL release 4 January 2001 NASA's Cassini spacecraft has continued collecting new scientific information from Jupiter's environs every day since making its closest approach to the giant planet on December 30, 2000, and is scheduled to keep studying the Jupiter system for another three months while proceeding on toward Saturn. "The flyby went smoothly, and the spacecraft is operating flawlessly again," said Bob Mitchell, Cassini program manager at NASA's Jet Propulsion Laboratory, Pasadena, CA. This week's targets of observation by Cassini begin with Jupiter's atmosphere and rings. Between January 5 and January 12, the moons Io, Europa and Ganymede will each be examined while in eclipse for information that their faint airglows can reveal about those moons' tenuous atmospheres. Today (Thursday), Cassini is measuring natural radio emissions from Jupiter's radiation belts, a research project that will also draw upon results from Earth-based radio telescope observations by students in 25 middle schools and high schools in 13 states. (For information on the student project, see http://www.jpl.nasa.gov/releases/2000/gavrtjupiter.html.) The flyby of Jupiter, at a distance of about 9.7 million kilometers (6 million miles), gave Cassini a boost from Jupiter's gravity that accelerated the spacecraft by about 2 kilometers per second (about 4,500 miles per hour) and will enable it to reach its ultimate destination, Saturn, in July 2004. A higher-than-normal drag that was detected on one of Cassini's reaction wheels more than two weeks ago has not reappeared. The reaction wheels are used to rotate the spacecraft in different directions, and the problem led to suspension from December 19 to December 28 of scientific observations that would have required pointing the spacecraft, such as for taking pictures. "That problem appears to be behind us, except that we have an extra workload to prevent recurrence of the conditions we think caused it," Mitchell said. Mission engineers believe that the excessive friction at one reaction wheel resulted from lessened lubrication after prolonged operation at relatively low speed. Operating the wheel at higher speeds apparently restored proper dispersal of the lubricant. The Cassini flight team is developing procedures for avoiding prolonged operation of the reaction wheels at relatively low speeds. Cassini is a cooperative mission of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages Cassini for NASA's Office of Space Science, Washington, DC. Additional information about Cassini is available online at http://www.jpl.nasa.gov/cassini. --------------------------------------------------------------------- THIS WEEK ON GALILEO JPL release 1-7 January 2001 Happy New Year! Galileo's first day of 2001 sees the completion of the few remaining remote-sensing observations planned for this encounter. The remainder of the week is spent primarily in completing week 10 of a 14-week-long survey of the Jovian magnetosphere. Galileo's Fields and Particles instruments are performing the survey. The spacecraft performs one navigation activity this week, and one engineering activity. On Tuesday, Galileo makes a small flight path adjustment. On Wednesday, the spacecraft executes a small turn to keep its radio antenna pointed toward Earth. The Solid-State Imaging camera (SSI) performs Monday's remaining remote sensing observations. The first two observations focus on a turbulent region just northwest of Jupiter's Great Red Spot. In observations performed in previous orbits, this particular region of Jupiter's atmosphere has been the site of very active thunderstorms. The observations performed today are the last of a series taken over four Jupiter rotations, which will enable scientists to study the evolution of these storms over long time scales. Jupiter rotates once every 10 hours. Observations during the previous three rotations were made yesterday. SSI also performs three observations of Jupiter's main ring. These images will allow scientists to determine the vertical structure of the ring and also shed light on some unexpected patchiness seen in the ring in previous observations. The Fields and Particles instruments on Galileo are the Dust Detector, Energetic Particle Detector, Heavy Ion Counter, Magnetometer, Plasma Detector, and Plasma Wave instrument. One of the themes of this encounter has been their 14-week survey of the Jovian magnetosphere, performed in conjunction with instruments on the Cassini spacecraft. The survey data obtained by the Galileo instruments are being occasionally stored on Galileo's onboard tape recorder in order to keep the survey continuous. Typically, magnetospheric data are collected in real time, which means they are almost immediately packaged and transmitted to Earth. However, when radio antennas of the Deep Space Network (DSN) are being used by other spacecraft, Galileo has a data buffer (a section of computer memory) which can store up to seven hours of survey data at one time. The tape recorder is necessary because some gaps in DSN tracking are longer than seven hours. In these cases, the contents of the data buffer are dumped to the tape recorder. These data are planned for playback, along with other recorded data, in a few weeks, at the completion of the 14-week survey. This week, Galileo will use its tape recorder five times. For more information on the Galileo spacecraft and its mission to Jupiter, please visit the Galileo home page at one of the following URL's: http://galileo.jpl.nasa.gov http://www.jpl.nasa.gov/galileo --------------------------------------------------------------------- ISS STATUS REPORT JSC release 3 January 2000 The Expedition One crew moved into its tenth week in orbit today aboard the International Space Station (ISS) as preparations stepped into high gear for the launch of the next Shuttle assembly flight to the outpost. Commander Bill Shepherd, Pilot Yuri Gidzenko and Flight Engineer Sergei Krikalev conducted biomedical and engineering experiments, Station systems maintenance and exercise this week, reporting that everything is proceeding smoothly more than halfway through their stay aboard the ISS. The only technical issue being addressed by Russian flight controllers involves a minor problem with battery three in the Zvezda Service Module, which was temporarily taken offline to enable Krikalev to check connector pins from the battery itself to a current converter unit behind one of the panels in the Station's living quarters. The battery experienced a small drop in current flow, but has no impact on Station operations. All other batteries in Zvezda and the Zarya module are functioning normally as they draw power from the U.S. P6 solar arrays mounted on top of the Station's Unity module. The huge U.S. solar arrays are providing more than ample power for all Station systems. Because the sun is shining obliquely to the Russian module solar arrays this week due to its angle relative to the Earth, Russian controllers decided to reduce the power output of the Elektron oxygen generation system in Zvezda to conserve electricity. One or two solid fuel oxygen generation canisters will be activated today and tomorrow to augment the output of oxygen on board the ISS until the Elektron is returned to full power Friday when the sun is in a more favorable angle to the solar arrays of both Zvezda and Zarya. All environmental systems on the ISS are functioning normally. Later this week, Shepherd, Gidzenko and Krikalev will review flight plans for the upcoming mission of Atlantis to the ISS to deliver the U.S. Laboratory Destiny, the cornerstone of scientific research for years to come on the Station. Today, Atlantis was transported to Launch Pad 39-A at the Kennedy Space Center for final prelaunch preparations leading to liftoff in about three weeks on the first Shuttle mission of 2001. Atlantis' five astronauts, Commander Ken Cockrell, Pilot Mark Polansky and Mission Specialists Bob Curbeam, Marsha Ivins and Tom Jones will conduct a variety of countdown dress rehearsal procedures later this week at the Cape, culminating in a simulated launch countdown Saturday morning with the crew on board the Shuttle. Launch of Atlantis to bring Destiny to the ISS is targeted for no earlier than January 19. Next week, NASA Shuttle and ISS managers will hold their traditional Flight Readiness Review to set a firm launch date for Atlantis' mission to the Station. The International Space Station continues to operate in excellent shape as it orbits the Earth every 90 minutes at an altitude of 230 statute miles. The next Expedition One status report will be issued on Wednesday, January 10, or sooner, if developments warrant. --------------------------------------------------------------------- STARDUST STATUS REPORT JPL release 5 January 2001 During the holiday period there were numerous Deep Space Network (DSN) tracking passes. All subsystems onboard the spacecraft are performing normally. The Stardust spacecraft is within 4,000,000 km from the Earth and closing rapidly. The spacecraft will make its closest approach to Earth on January 15, at 11:15 Universal time. There is a small possibility that Stardust may be visible from Earth after flyby using sophisticated telescopes with CCD detectors. Additional information will be available on the Stardust web site. In preparation for the Earth Gravity Assist, the Command Loss Timer was changed to three days from its usual value of nine days. The CLT is an onboard countdown clock based on the last successful command received by the spacecraft. When the CLT reaches zero or when there is no communication from Earth for nine days-the safe mode executive assumes there is a problem somewhere in the spacecraft's uplink path and requests safe mode. The SME will then autonomously swap components in the uplink path, pausing in between swaps, until a command is received. Since Stardust is rapidly approaching EGA, the command loss time was reduced to three days to allow a faster recovery in the unlikely failure of an uplink component. This strategy will allow the spacecraft team to respond to a failure and ensure that critical commands are successfully sent to the spacecraft in a timely manner. Also, a timer in the SME was changed to ensure that if a safe mode entry occurs, the spacecraft will remain pointed at the Sun and not attempt to communicate with the Earth. If the spacecraft enters safe mode just prior to the closest approach, the batteries would reach their low state of charge limit (50%) because the Earth and Sun are 180 degrees apart. If the spacecraft enters safe mode after closest approach, the SME will command the spacecraft to a power-friendly communications attitude. This change will ensure the spacecraft remains in a safe attitude, pointed at the Sun, until the spacecraft team commands it to "phone home". This morning, Stardust successfully completed Trajectory Correction Maneuver #5 (TCM-5), the final targeting for Earth flyby in 10 days. Five Navigation Camera images were taken to assess camera performance after the 2nd heating sequence where both the CCD and mirror motor heaters were turned on for about 1 month. These images will be played back later today. The spacecraft will then be left alone until after Earth flyby. On January 12, a live interview with Stardust project manager Tom Duxbury will be shown on NASA TV, followed by an animation of the Earth flyby and pictures of the spacecraft. To see the interview, tune to satellite GE-2, Transponder 9C at 85 degrees West longitude, with vertical polarization. Frequency is on 3880.0 megahertz with audio on 6.8 megahertz. For more information on the Stardust mission-the first ever comet sample return mission-please visit the Stardust home page at http://stardust.jpl.nasa.gov. --------------------------------------------------------------------- End Marsbugs, Volume 8, Number 1